Today, various types of networks and internet based applications are developed using mobile agent technology. This technology is one of the suitable mechanisms for distributed environment. However, still there is a lack of practical usage in real time systems, because of its security. Most of the existing techniques are focusing on mobile agent's security. Also, it is necessary to protect mobile agent platform against various types of attacks done by the malicious agents. Among the various types of attacks, spam attack is a type of attack carried out by the malicious agent. The spam agent attempts to consume more resources or to make a particular facility unavailable to genuine entities. Attacks in this category are usually referred as Denial of Service (DoS) attack.